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Linke F, Johnson JEC, Kern S, Bennett CD, Lourdusamy A, Lea D, Clifford SC, Merry CLR, Stolnik S, Alexander MR, Peet AC, Scurr DJ, Griffiths RL, Grabowska AM, Kerr ID, Coyle B. Identifying new biomarkers of aggressive Group 3 and SHH medulloblastoma using 3D hydrogel models, single cell RNA sequencing and 3D OrbiSIMS imaging. Acta Neuropathol Commun 2023; 11:6. [PMID: 36631900 PMCID: PMC9835248 DOI: 10.1186/s40478-022-01496-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 12/19/2022] [Indexed: 01/13/2023] Open
Abstract
The most common malignant brain tumour in children, medulloblastoma (MB), is subdivided into four clinically relevant molecular subgroups, although targeted therapy options informed by understanding of different cellular features are lacking. Here, by comparing the most aggressive subgroup (Group 3) with the intermediate (SHH) subgroup, we identify crucial differences in tumour heterogeneity, including unique metabolism-driven subpopulations in Group 3 and matrix-producing subpopulations in SHH. To analyse tumour heterogeneity, we profiled individual tumour nodules at the cellular level in 3D MB hydrogel models, which recapitulate subgroup specific phenotypes, by single cell RNA sequencing (scRNAseq) and 3D OrbiTrap Secondary Ion Mass Spectrometry (3D OrbiSIMS) imaging. In addition to identifying known metabolites characteristic of MB, we observed intra- and internodular heterogeneity and identified subgroup-specific tumour subpopulations. We showed that extracellular matrix factors and adhesion pathways defined unique SHH subpopulations, and made up a distinct shell-like structure of sulphur-containing species, comprising a combination of small leucine-rich proteoglycans (SLRPs) including the collagen organiser lumican. In contrast, the Group 3 tumour model was characterized by multiple subpopulations with greatly enhanced oxidative phosphorylation and tricarboxylic acid (TCA) cycle activity. Extensive TCA cycle metabolite measurements revealed very high levels of succinate and fumarate with malate levels almost undetectable particularly in Group 3 tumour models. In patients, high fumarate levels (NMR spectroscopy) alongside activated stress response pathways and high Nuclear Factor Erythroid 2-Related Factor 2 (NRF2; gene expression analyses) were associated with poorer survival. Based on these findings we predicted and confirmed that NRF2 inhibition increased sensitivity to vincristine in a long-term 3D drug treatment assay of Group 3 MB. Thus, by combining scRNAseq and 3D OrbiSIMS in a relevant model system we were able to define MB subgroup heterogeneity at the single cell level and elucidate new druggable biomarkers for aggressive Group 3 and low-risk SHH MB.
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Affiliation(s)
- Franziska Linke
- Children's Brain Tumour Research Centre, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, UK
| | - James E C Johnson
- Children's Brain Tumour Research Centre, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, UK
| | - Stefanie Kern
- School of Pharmacy, University of Nottingham, Nottingham, UK
| | - Christopher D Bennett
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Birmingham Children's Hospital, Birmingham, UK
| | - Anbarasu Lourdusamy
- Children's Brain Tumour Research Centre, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, UK
| | - Daniel Lea
- Digital Research Service, University of Nottingham, Nottingham, UK
| | - Steven C Clifford
- Wolfson Childhood Cancer Research Centre, Translational & Clinical Research Institute, Newcastle University Centre for Cancer, Newcastle Upon Tyne, NE1 7RU, UK
| | - Catherine L R Merry
- School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, UK
| | - Snow Stolnik
- School of Pharmacy, University of Nottingham, Nottingham, UK
| | | | - Andrew C Peet
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Birmingham Children's Hospital, Birmingham, UK
| | - David J Scurr
- School of Pharmacy, University of Nottingham, Nottingham, UK
| | | | - Anna M Grabowska
- School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, UK
| | - Ian D Kerr
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Beth Coyle
- Children's Brain Tumour Research Centre, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, UK.
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Rose H, Li H, Bennett CD, Novak J, Sun Y, MacPherson L, Avula S, Arvanitis T, Clark C, Bailey S, Mitra D, Auer D, Grundy R, Peet A. The role of diffusion tensor imaging metrics in machine learning-based characterisation of paediatric brain tumors and their practicality for multicentre clinical assessment. Neuro Oncol 2021. [DOI: 10.1093/neuonc/noab195.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Aims
Magnetic resonance imaging (MRI) is a valuable tool for non-invasive diagnosis of paediatric brain tumours. The rarity of the disease dictates multi-centre studies and imaging biomarkers that are robust to protocol variability. We investigated diffusion tensor MRI (DT-MRI), combined with machine learning, as an aid to diagnosis and evaluated the robustness of the imaging metrics.
Method
A multi-centre cohort of 52 clinical DT-MRI scans (20 medulloblastomas (MB), 21 pilocytic astrocytomas (PA), 11 ependymomas (EP)) were analysed retrospectively. Histograms for regions of solid tumour for fractional anisotropy (FA), mean diffusivity (MD), pure anisotropic diffusion (q) and pure isotropic diffusion (p) were compared to assess diagnostic capability. Linear discriminate analysis (LDA) was used for classification and validated using leave-one-out-cross-validation (LOOCV).
Results
Histogram medians for FA, MD, q and p were all different between tumor groups (P<.0001, Kruskal Wallis test). Median MD, p and q values were highest in PA, then EP and lowest in MB (P<.0001, Pairwise Wilcox test). FA median was higher for EP than PA (P=.004) with no significant difference between EP and MB (P=.591). ROC analysis showed that median MD, q and p perform best as a diagnostic marker (AUC= 0.92 to 0.99). LOOCV showed an overall accuracy of the LDA classification, ranging between 67% - 87%. FA values were highly dependent on protocol parameters, whereas pure anisotropic diffusion, q, was not.
Conclusion
DT-MRI metrics from multi-centre acquisitions can classify paediatric brain tumours. FA is the least robust metric to protocol variability and q provides the most robust quantification of anisotropic behaviour.
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Affiliation(s)
- Heather Rose
- Institute of Cancer and Genomic sciences, The University of Birmingham
| | - Huijun Li
- Birmingham Children’s Hospital
- Children’s Hospital of Nanjing Medical University, Nanjing
| | | | - Jan Novak
- Birmingham Children’s Hospital
- School of Life and Health Sciences, Aston University
| | - Yu Sun
- Institute of Cancer and Genomic sciences, The University of Birmingham
- Birmingham Children’s Hospital
| | | | | | | | | | - Simon Bailey
- Sir James Spence Institute of Child Health, Royal Victoria Infirmary
| | - Dipayan Mitra
- Neuroradiology Department, Newcastle upon Tyne Hospitals, Newcastle upon Tyne
| | - Dorothee Auer
- Sir Peter Mansfield Imaging Centre, University of Nottingham
| | - Richard Grundy
- The Children’s Brain Tumour Research Centre, University of Nottingham
| | - Andrew Peet
- Institute of Cancer and Genomic sciences, The University of Birmingham
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3
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Badodi S, Pomella N, Zhang X, Morrison G, Pollard SM, Bennett CD, Clifford SC, Peet A, Marino S. EMBR-10. INOSITOL TREATMENT INHIBITS MEDULLOBLASTOMA THROUGH SUPPRESSION OF EPIGENETIC-DRIVEN METABOLIC ADAPTATION. Neuro Oncol 2021. [PMCID: PMC8168266 DOI: 10.1093/neuonc/noab090.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Medulloblastoma (MB) is the most common paediatric malignant brain tumour and is classified into four distinct molecular subgroups (WNT, SHH, G3 and G4), each of them further subdivided into subtypes with different prognosis and responses to therapy. Deregulation of chromatin modifier genes plays an essential role in MB, particularly in the G4 subgroup, the least understood of all subgroups, despite being the most common and associated with poor prognosis. A BMI1High; CHD7Low molecular signature identifies patients with poor survival within this subgroup. We show that BMI1High; CHD7Low mediates a novel epigenetic regulation of inositol metabolism in both G4 MB cells and patients. These tumours display hyperactivation of the AKT/mTOR pathway which leads to energetic rewiring characterized by enhanced glycolytic capacity and reduced mitochondrial function. We demonstrate that inositol administration counteracts this metabolic alteration, impairs MB proliferation in vitro and significantly extends survival in an in vivo pre-clinical model. Moreover, inositol synergises with cisplatin, a chemotherapy agent currently used in MB treatment, enhancing its therapeutic effect in vivo. Importantly, cerebellar neural stem cells bearing the BMI1High; CHD7Low signature do not show metabolic adaptation and are thus resistant to inositol treatment, highlighting a fundamental difference between normal and neoplastic metabolism in the developing cerebellum. In summary, we have identified an actionable vulnerability in a pre-clinical setting modelling a molecularly defined group of MB patients, the translational value of which can now be explored in signature-matched clinical trials in MB.
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Affiliation(s)
- Sara Badodi
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Nicola Pomella
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Xinyu Zhang
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Gillian Morrison
- Centre for Regenerative Medicine & Cancer Research UK Edinburgh Centre, The University of Edinburgh, Edinburgh, UK
| | - Steve M Pollard
- Centre for Regenerative Medicine & Cancer Research UK Edinburgh Centre, The University of Edinburgh, Edinburgh, UK
| | - Christopher D Bennett
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Birmingham Children’s Hospital, Birmingham, UK
| | - Steven C Clifford
- Newcastle University Centre for Cancer, Wolfson Childhood Cancer Research Centre, Translational and Clinical Research Institute, Newcastle upon Tyne, UK
| | - Andrew Peet
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Birmingham Children’s Hospital, Birmingham, UK
| | - Silvia Marino
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
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Badodi S, Pomella N, Zhang X, Rosser G, Whittingham J, Niklison-Chirou MV, Lim YM, Brandner S, Morrison G, Pollard SM, Bennett CD, Clifford SC, Peet A, Basson MA, Marino S. Inositol treatment inhibits medulloblastoma through suppression of epigenetic-driven metabolic adaptation. Nat Commun 2021; 12:2148. [PMID: 33846320 PMCID: PMC8042111 DOI: 10.1038/s41467-021-22379-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 03/12/2021] [Indexed: 12/11/2022] Open
Abstract
Deregulation of chromatin modifiers plays an essential role in the pathogenesis of medulloblastoma, the most common paediatric malignant brain tumour. Here, we identify a BMI1-dependent sensitivity to deregulation of inositol metabolism in a proportion of medulloblastoma. We demonstrate mTOR pathway activation and metabolic adaptation specifically in medulloblastoma of the molecular subgroup G4 characterised by a BMI1High;CHD7Low signature and show this can be counteracted by IP6 treatment. Finally, we demonstrate that IP6 synergises with cisplatin to enhance its cytotoxicity in vitro and extends survival in a pre-clinical BMI1High;CHD7Low xenograft model.
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Affiliation(s)
- Sara Badodi
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Nicola Pomella
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Xinyu Zhang
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Gabriel Rosser
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - John Whittingham
- Centre for Craniofacial and Regenerative Biology, King's College London, London, UK
| | - Maria Victoria Niklison-Chirou
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
- Centre for Therapeutic Innovation (CTI-Bath), Department of Pharmacy & Pharmacology, University of Bath, Bath, UK
| | - Yau Mun Lim
- UCL Queen Square Institute of Neurology and The National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London, UK
| | - Sebastian Brandner
- UCL Queen Square Institute of Neurology and The National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London, UK
| | - Gillian Morrison
- Centre for Regenerative Medicine & Cancer Research UK Edinburgh Centre, The University of Edinburgh, Edinburgh, UK
| | - Steven M Pollard
- Centre for Regenerative Medicine & Cancer Research UK Edinburgh Centre, The University of Edinburgh, Edinburgh, UK
| | - Christopher D Bennett
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Birmingham Women and Children's Hospital, Birmingham, UK
| | - Steven C Clifford
- Newcastle University Centre for Cancer, Wolfson Childhood Cancer Research Centre, Translational and Clinical Research Institute, Newcastle upon Tyne, UK
| | - Andrew Peet
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Birmingham Women and Children's Hospital, Birmingham, UK
| | - M Albert Basson
- Centre for Craniofacial and Regenerative Biology, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
| | - Silvia Marino
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
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5
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Bennett CD, Gill SK, Kohe SE, Wilson MP, Davies NP, Arvanitis TN, Tennant DA, Peet AC. Ex vivo metabolite profiling of paediatric central nervous system tumours reveals prognostic markers. Sci Rep 2019; 9:10473. [PMID: 31324817 PMCID: PMC6642141 DOI: 10.1038/s41598-019-45900-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 06/03/2019] [Indexed: 02/06/2023] Open
Abstract
Brain tumours are the most common cause of cancer death in children. Molecular studies have greatly improved our understanding of these tumours but tumour metabolism is underexplored. Metabolites measured in vivo have been reported as prognostic biomarkers of these tumours but analysis of surgically resected tumour tissue allows a more extensive set of metabolites to be measured aiding biomarker discovery and providing validation of in vivo findings. In this study, metabolites were quantified across a range of paediatric brain tumours using 1H-High-Resolution Magic Angle Spinning nuclear magnetic resonance spectroscopy (HR-MAS) and their prognostic potential investigated. HR-MAS was performed on pre-treatment frozen tumour tissue from a single centre. Univariate and multivariate Cox regression was used to examine the ability of metabolites to predict survival. The models were cross validated using C-indices and further validated by splitting the cohort into two. Higher concentrations of glutamine were predictive of a longer overall survival, whilst higher concentrations of lipids were predictive of a shorter overall survival. These metabolites were predictive independent of diagnosis, as demonstrated in multivariate Cox regression models. Whilst accurate quantification of metabolites such as glutamine in vivo is challenging, metabolites show promise as prognostic markers due to development of optimised detection methods and increasing use of 3 T clinical scanners.
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Affiliation(s)
- Christopher D Bennett
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom
- Birmingham Women's and Children's Hospital NHS Foundation Trust, Birmingham, United Kingdom
| | - Simrandip K Gill
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom
- Birmingham Women's and Children's Hospital NHS Foundation Trust, Birmingham, United Kingdom
| | - Sarah E Kohe
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom
- Birmingham Women's and Children's Hospital NHS Foundation Trust, Birmingham, United Kingdom
| | - Martin P Wilson
- Birmingham University Imaging Centre, School of Psychology, University of Birmingham, Birmingham, United Kingdom
| | - Nigel P Davies
- University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom
| | - Theodoros N Arvanitis
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom
- Birmingham Women's and Children's Hospital NHS Foundation Trust, Birmingham, United Kingdom
- Institute of Digital Healthcare, WMG, University of Warwick, Coventry, United Kingdom
| | - Daniel A Tennant
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, UK
| | - Andrew C Peet
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom.
- Birmingham Women's and Children's Hospital NHS Foundation Trust, Birmingham, United Kingdom.
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6
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Kohe SE, Babourina-Brooks B, Scerif F, Hicks D, Schwalbe EC, Crosier S, Lindsey J, Adiamah M, Storer LCD, Lourdusamy A, Gill SK, Bennett CD, Wilson M, Avula S, Mitra D, Dineen R, Bailey S, Williamson D, Grundy RG, Clifford SC, Peet AC. MBRS-29. IN-VIVO METABOLITE PROFILES FOR THE NON-INVASIVE AND RAPID IDENTIFICATION OF MOLECULAR SUBGROUP IN MEDULLOBLASTOMA. Neuro Oncol 2018. [DOI: 10.1093/neuonc/noy059.474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Sarah E Kohe
- Institute of Cancer and Genomic SciencesUniversity of Birmingham, Birmingham, UK
- Birmingham Womens and Childrens NHS Foundation Trust, Birmingham, UK
| | - Ben Babourina-Brooks
- Institute of Cancer and Genomic SciencesUniversity of Birmingham, Birmingham, UK
- Birmingham Womens and Childrens NHS Foundation Trust, Birmingham, UK
| | - Fatma Scerif
- Northern Institute for Cancer Research, Newcastle University, Newcastle, UK
| | - Debbie Hicks
- Northern Institute for Cancer Research, Newcastle University, Newcastle, UK
| | - Ed C Schwalbe
- Northern Institute for Cancer Research, Newcastle University, Newcastle, UK
| | - Stephen Crosier
- Northern Institute for Cancer Research, Newcastle University, Newcastle, UK
| | - Janet Lindsey
- Northern Institute for Cancer Research, Newcastle University, Newcastle, UK
| | - Magretta Adiamah
- Northern Institute for Cancer Research, Newcastle University, Newcastle, UK
| | - Lisa C D Storer
- Children’s Brain Tumour Research Centre, University of Nottingham, Nottingham, UK
| | - Anbarasu Lourdusamy
- Children’s Brain Tumour Research Centre, University of Nottingham, Nottingham, UK
| | - Simrandip K Gill
- Institute of Cancer and Genomic SciencesUniversity of Birmingham, Birmingham, UK
- Birmingham Womens and Childrens NHS Foundation Trust, Birmingham, UK
| | - Christopher D Bennett
- Institute of Cancer and Genomic SciencesUniversity of Birmingham, Birmingham, UK
- Birmingham Womens and Childrens NHS Foundation Trust, Birmingham, UK
| | - Martin Wilson
- Institute of Cancer and Genomic SciencesUniversity of Birmingham, Birmingham, UK
- Birmingham Womens and Childrens NHS Foundation Trust, Birmingham, UK
| | | | - Dipayan Mitra
- Newcastle Hospitals NHS Foundation Trust, Newcastle, UK
| | - Rob Dineen
- Children’s Brain Tumour Research Centre, University of Nottingham, Nottingham, UK
| | - Simon Bailey
- Northern Institute for Cancer Research, Newcastle University, Newcastle, UK
- Great North Children’s Hospital, Newcastle, UK
| | - Daniel Williamson
- Northern Institute for Cancer Research, Newcastle University, Newcastle, UK
| | - Richard G Grundy
- Children’s Brain Tumour Research Centre, University of Nottingham, Nottingham, UK
| | - Steven C Clifford
- Northern Institute for Cancer Research, Newcastle University, Newcastle, UK
| | - Andrew C Peet
- Institute of Cancer and Genomic SciencesUniversity of Birmingham, Birmingham, UK
- Birmingham Womens and Childrens NHS Foundation Trust, Birmingham, UK
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7
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Ghosh N, Manias K, Bennett CD, Oates A, English M, Peet A, Adamski J. LGG-29. RESIDUAL TUMOUR SIZE AS A PREDICTOR OF PROGRESSION FOR PAEDIATRIC LOW-GRADE GLIOMA. Neuro Oncol 2018. [DOI: 10.1093/neuonc/noy059.370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | | | | | - Adam Oates
- Birmingham Children’s Hospital, Birmingham, UK
| | | | - Andrew Peet
- Birmingham Children’s Hospital, Birmingham, UK
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8
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Kohe SE, Bennett CD, Gill SK, Wilson M, McConville C, Peet AC. Metabolic profiling of the three neural derived embryonal pediatric tumors retinoblastoma, neuroblastoma and medulloblastoma, identifies distinct metabolic profiles. Oncotarget 2018. [PMID: 29541417 PMCID: PMC5834290 DOI: 10.18632/oncotarget.24168] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The rare pediatric embryonal tumors retinoblastoma, medulloblastoma and neuroblastoma derive from neuroectodermal tissue and share similar histopathological features despite different anatomical locations and diverse clinical outcomes. As metabolism can reflect genetic and histological features, we investigated whether the metabolism of embryonal tumors reflects their similar histology, shared developmental and neural origins, or tumor location. We undertook metabolic profiling on 50 retinoblastoma, 39 medulloblastoma and 70 neuroblastoma using high resolution magic angle spinning magnetic resonance spectroscopy (1H-MRS). Mean metabolite concentrations identified several metabolites that were significantly different between the tumor groups including taurine, hypotaurine, glutamate, glutamine, GABA, phosphocholine, N-acetylaspartate, creatine, glycine and myoinositol, p < 0.0017. Unsupervised multivariate analysis found that each tumor group clustered separately, with a unique metabolic profile, influenced by their underlying clinical diversity. Taurine was notably high in all tumors consistent with prior evidence from embryonal tumors. Retinoblastoma and medulloblastoma were more metabolically similar, sharing features associated with the central nervous system (CNS). Neuroblastoma had features consistent with neural tissue, but also contained significantly higher myoinositol and altered glutamate-glutamine ratio, suggestive of differences in the underlying metabolism of embryonal tumors located outside of the CNS. Despite the histological similarities and shared neural metabolic features, we show that individual neuroectodermal derived embryonal tumors can be distinguished by tissue metabolic profile. Pathway analysis suggests the alanine-aspartate-glutamate and taurine-hypotaurine metabolic pathways may be the most pertinent pathways to investigate for novel therapeutic strategies. This work strengthens our understanding of the biology and metabolic pathways underlying neuroectodermal derived embryonal tumors of childhood.
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Affiliation(s)
- Sarah E Kohe
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom.,Birmingham Children's Hospital, NHS Foundation Trust, Birmingham, United Kingdom
| | - Christopher D Bennett
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom.,Birmingham Children's Hospital, NHS Foundation Trust, Birmingham, United Kingdom
| | - Simrandip K Gill
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom.,Birmingham Children's Hospital, NHS Foundation Trust, Birmingham, United Kingdom
| | - Martin Wilson
- Centre for Human Brain Health, School of Psychology, University of Birmingham, Birmingham, United Kingdom
| | - Carmel McConville
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Andrew C Peet
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom.,Birmingham Children's Hospital, NHS Foundation Trust, Birmingham, United Kingdom
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9
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Gill SK, Bennett CD, Kohe S, Wilson M, Davies NP, Arvanitis TN. TB-21METABOLISM AS A PREDICTOR OF SURVIVAL IN CHILDREN'S BRAIN TUMOURS. Neuro Oncol 2016. [DOI: 10.1093/neuonc/now084.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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10
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Bennett CD, Gill SK, Kohe S, Zarinabad N, Davies NP, Wilson M, Storer L, Ritzmann T, Paine S, Scott I, Nicklaus-Wollenteit I, Grundy RG, Peet AC. TB-26TISSUE METABOLITE PROFILES IN THE CHARACTERISATION AND DIAGNOSIS OF CHILDHOOD POSTERIOR FOSSA TUMOURS. Neuro Oncol 2016. [DOI: 10.1093/neuonc/now084.18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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11
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Kohe S, Gill SK, Hicks D, Schwalbe EC, Crosier S, Storer L, Lourdusamy A, Bennett CD, Wilson M, Bailey S, Williamson D, Grundy RG, Clifford SC, Peet AC. MB-84IDENTIFICATION OF MEDULLOBLASTOMA MOLECULAR SUBGROUPS USING METABOLITE PROFILES. Neuro Oncol 2016. [DOI: 10.1093/neuonc/now076.80] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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12
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Bennett CD, Campbell MN, Cook CJ, Eyre DJ, Nay LM, Nielsen DR, Rasmussen RP, Bernard PS. The LightTyper: high-throughput genotyping using fluorescent melting curve analysis. Biotechniques 2003; 34:1288-92, 1294-5. [PMID: 12813898 DOI: 10.2144/03346pf01] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Instrumentation, chemistry, and software for high-throughput genotyping using fluorescent melting curves are described. The LightTyper system provides post-amplification genotyping within 10 min using samples in 96- or 384-well microplate formats. The system is homogenous because all reagents are added at the beginning of the reaction and there is no sample manipulation between amplification and genotyping. High-resolution melting curves are achieved by slow and steady heating. As samples are heated, panels of blue light-emitting diodes excite the probes, and fluorescence emission is acquired with a cooled charge-coupled device camera. A variety of probe chemistries are compatible for genotyping on the LightTyper, including dsDNA dyes, single-labeled probes, and fluorescence resonance energy transfer systems. Genotyping is performed automatically, and each sample is given a score reflecting the similarity of the genotype to the standards provided. Standard genotypes can be selected from within the run or imported from other files. Samples and genotypes can be grouped to allow multiple-allele detection on one or many samples. The utility of the LightTyper is illustrated by genotyping samples for the Factor V Leiden mutation and for mutations in the CFTR gene.
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13
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Abstract
The live performance from 19 to 43 wk of age of two strains of commercial White Leghorn hens fed two levels of whole barley (0 or 60%) and insoluble grit (0 or 4 g/bird per wk) was compared. The 0 and 60% whole barley diets differed only in feed form and were formulated to the same nutrient specifications. No dilution of nutrients or ingredients occurred. The 0% whole barley diet was fed in mash form. The 60% whole barley diet was fed as whole grain and mash concentrate blended into a complete diet and fed in the same feed trough. Feeding whole barley reduced egg production, feed efficiency, and egg specific gravity and increased feed intake, egg weight, and body weight gain. Access to insoluble grit had no effect on any of the production variables measured. The two strains of hens responded similarly to whole barley but differed in feed intake, feed efficiency, egg weight, egg specific gravity, and body weight gain. Feeding whole barley combined with a mash concentrate depressed hen performance compared to birds fed a similar diet in mash form. Strain of hen and access to insoluble grit did not alter the response to feeding whole barley.
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Affiliation(s)
- C D Bennett
- Department of Animal & Poultry Science, University of Saskatchewan, Saskatchewan, Canada, S7N 5A8.
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14
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Abstract
Live performance to 96 d was compared for 1,584 turkey toms reared on diets containing four levels of whole barley and two levels of insoluble grit (0 or 9 g/bird per wk). Nutrient specifications for all diets were similar. The six dietary treatments were 1) 0% whole barley plus grit, 2) Treatment 1 minus grit, 3) grit plus 5% whole barley at 0 d increasing to 35% by 19 d, 4) grit plus 5% whole barley at 0 d increasing to 50% by 19 d, 5) Treatment 4 minus grit, and 6) grit plus 5% whole barley at 19 d increasing to 50% by 40 d. The concentrate blended with the whole barley was fed as crumbles or pellets. Nutrients were not diluted. Compared to the control treatments, feeding 35% or more whole barley temporarily reduced weight gain and increased feed:gain prior to 68 d. Cumulative weight gain was reduced in Treatments 3 and 5 compared to treatments in which no barley was fed. Cumulative feed:gain was increased in Treatment 5 compared to Treatments 2 and 3. Total mortality and leg and skeletal problems were reduced in treatments where whole grain slowed early growth rate. Feeding grit had no effect on the live performance of birds fed similar levels of whole barley. In treatments in which whole barley was introduced at 0 d, gizzard pH was decreased at 18 d, and gizzard weight was increased at 32 d. Jejunal viscosity was unaffected by dietary treatment.
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Affiliation(s)
- C D Bennett
- Department of Animal & Poultry Science, University of Saskatchewan, Saskatchewan, Canada, S7N 5A8.
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15
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Abstract
The effect of grain form (whole, mash, or pelleted) on the live performance of broiler chickens was determined. In the first trial, six regimens compared the feeding of whole wheat: 1) 0% of diet for the whole trial (0 to 48 d); 2) 5% at 6 d, 20% at 13 d, 35% at 27 d; 3) 5% at 6 d, 35% at 13 d, 50% at 27 d; 4) 5% at 0 d, 20% at 6 d, 35% at 13 d, 50% at 27 d; 5) 5% at 6 d, 50% at 13 d, 65% at 27 d; and 6) 5% at 0 d, 20% at 6 d, 50% at 13 d, 65% at 27d. Each feeding regimen was replicated with steam-pelleted and mash supplements. None of the feed was diluted. The second trial was similar, except that whole barley was fed instead of whole wheat. Feeding mash supplements slowed growth at all ages and lowered mortality caused by sudden death syndrome and ascites plus right heart failure. Cumulative feed:gain was increased by feeding mash supplements in Trial 1. Total weight gain was unaffected by feeding whole wheat but was decreased by most levels of whole barley. Whole-grain diets increased cumulative feed:gain. Feeding whole wheat decreased skeletal problems. Whole-grain diets increased gizzard size but did not alter carcass yield. Feeding whole-grain and mash supplements caused at least a temporary loss in growth rate and feed efficiency but in some cases improved bird health.
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Affiliation(s)
- C D Bennett
- Department of Animal & Poultry Science, University of Saskatchewan, Canada.
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16
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Abstract
A study was completed to characterize the electrocardiographic (ECG) patterns of male broiler chickens. Data were collected from 300 commercial broilers. ECG readings were collected from all birds between 12 and 15 days of age and then twice more at 10-day intervals. The measurements. included heart rate and rhythm, QRS complex duration, amplitude and mean electrical axis (MEA), incidence of ascites and incidence of sudden death syndrome (SDS). Eight birds died from SDS and 4 birds died from ascites. Twelve birds were condemned for ascites at the processing plant. The overall population heart rate declined with age. Birds that died of SDS had a higher heart rate, whereas those that developed ascites had a lower heart rate than the remainder of the population. The normal MEA was found to be between 0 degree and 180 degrees. On average 30% of birds showed left or right QRS axis deviation, and this pattern was observed in 14 of the 16 birds that developed ascites. Several types of cardiac arrhythmias were observed, the most common being premature ventricular contractions (PVC). The incidence of PVC increased with age, ranging from 1% at 12-15 days of age to 8.9% at 32-35 days of age. QRS axis deviation was present in 5 SDS birds. It is concluded that some 30% of the broiler flock tested was at risk of developing heart failure or heart-related disease.
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Affiliation(s)
- A A Olkowski
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Canada
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17
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Towler DA, Bennett CD, Rodan GA. Activity of the rat osteocalcin basal promoter in osteoblastic cells is dependent upon homeodomain and CP1 binding motifs. Mol Endocrinol 1994; 8:614-24. [PMID: 7914673 DOI: 10.1210/mend.8.5.7914673] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
A detailed analysis of the transcriptional machinery responsible for osteoblast-specific gene expression should provide tools useful for understanding osteoblast commitment and differentiation. We have defined three cis-elements important for basal activity of the rat osteocalcin (OC) promoter, located at about -200 to -180, -170 to -138, and -121 to -64 relative to the transcription initiation site. A motif (TCTGATTGTGT) present in the region between -200 and -170 that binds a multisubunit CP1/NFY/CBF-like CAAT factor complex contributes significantly to high level basal activity and presumably functions as the CAAT box for the rat OC promoter. We show that the region -121 to 32 is sufficient to confer osteoblastic cell type specificity in transient transfection assays of cultured cell lines using luciferase as a reporter. The basal promoter is active in rodent osteoblastic cell lines, but not in rodent fibroblastic or muscle cell lines. Although the rat OC box (-100 to -74) contains a CAAT motif, we could not detect CP1-like CAAT factor binding to this region. In fact, we demonstrate that a Msx-1 (Hox 7.1) homeodomain binding motif (ACTAATTG; bottom strand) in the 3'-end of the rat OC box is necessary for high level activity of the rat OC basal promoter in osteoblastic cells. A nuclear factor that recognizes this motif appears to be present in osteoblastic ROS 17/2.8 cells, which produce OC, but not in fibroblastic ROS 25/1 cells, which fail to express OC. This ROS 17/2.8 nuclear factor also recognizes the A/T-rich DNA cognates of the homeodomain-containing POU family of transcription factors. Taken together, these data suggest that a ubiquitous CP1-like CAAT factor and a cell type-restricted homeodomain containing (Msx or POU family) transcription factor interact with the proximal rat OC promoter to direct appropriate basal OC transcription in osteoblastic cells.
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Affiliation(s)
- D A Towler
- Department of Bone Biology and Osteoporosis Research, Merck/MRL West Point, Pennsylvania 19486
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18
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Carroll SS, Olsen DB, Bennett CD, Gotlib L, Graham DJ, Condra JH, Stern AM, Shafer JA, Kuo LC. Inhibition of HIV-1 reverse transcriptase by pyridinone derivatives. Potency, binding characteristics, and effect of template sequence. J Biol Chem 1993; 268:276-81. [PMID: 7677997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The inhibition of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase by pyridinone compounds has been investigated using as templates synthetic RNA with sequences based on the HIV-1 genome sequence. In reactions catalyzed by the enzyme that incorporated more than one nucleotide per primer, inhibition by a representative pyridinone inhibitor, 3-[2-(1,3-benzoxazol-2-yl)ethyl]-5-ethyl-6-methyl-pyridin-2(1H)one (L-696,229), was noncompetitive against deoxynucleotide triphosphate. For reactions that incorporated one deoxynucleotide per primer, IC50 values ranged from 20 to 200 nM, depending on the position of incorporation of the incoming deoxynucleotide base on the template. Inhibition of synthesis on a set of four templates differing only at the template base complementary to the incoming nucleotide had similar IC50 values. These results demonstrate that inhibitory potency is dependent on the primary structure of the template and that inhibitory potency is largely independent of the identity of the incoming nucleotide base. The inhibition of HIV-1 reverse transcription by L-696,229 also displayed slow-binding characteristics. The slow-binding aspect was exploited to gauge the interaction between inhibitor and enzyme. By titrating the reduction in the extent of the burst of synthesis observed in a reaction incorporating dideoxythymidine monophosphate into poly(rA)-oligo(dT)18, the apparent equilibrium constant for dissociation of the reverse transcriptase-L-696,229 complex was estimated to be 400 nM.
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Affiliation(s)
- S S Carroll
- Department of Biological Chemistry, Merck Research Laboratories, West Point, Pennsylvania 19486
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19
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Bennett CD. Hydrogen phosphonate chemistry can be compatible with the large bottle update on the applied biosystems 380B DNA synthesizer. Biotechniques 1990; 8:618, 620. [PMID: 2357380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- C D Bennett
- Biological Chemistry Department, Merck Sharp and Dohme Research Laboratory, West Point, PA 19486
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20
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Abstract
Broiler breeder pullets were reared on a standard breeder-grower diet in accordance with breeder recommendations to 10 wk of age, with samples of the birds being selected for carcass analysis at 2, 3, 4, 5, 6, 7, 8 and 10 wk of age. At 10 wk of age, 264 pullets were assigned to one of three diets formulated to contain 15% CP and to provide 2,550, 2,800 or 3,080 kcal of ME per kg. The birds on the 2,800-kcal diet were fed to attain the body weight recommended by the breeder; the birds on the other diets received the same feed allotment. At 14, 16, 18, 20, 22, and 24 wk of age, 12 birds per treatment were slaughtered for carcass analysis. All of the birds were light-stimulated at 20 wk of age. From 2 to 10 wk of age, carcass analysis of the feed-restricted pullets revealed a relatively constant protein content, 20 to 21%, accompanied by a declining proportion of fat. Feeding a high-energy diet from 10 to 24 wk of age increased body weight and the absolute and proportional content of fat. The percentage of body protein was largely unaffected by the diet, but there was a consistent effect on fat content (P less than .05). The body fat and protein contents were highly correlated with body weight.
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Affiliation(s)
- C D Bennett
- Department of Animal and Poultry Science, University of Guelph, Ontario, Canada
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21
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Gan ZR, Condra JH, Gould RJ, Zivin RA, Bennett CD, Jacobs JW, Friedman PA, Polokoff MA. High-level expression in Escherichia coli of a chemically synthesized gene for [Leu-28]echistatin. Gene X 1989; 79:159-66. [PMID: 2673933 DOI: 10.1016/0378-1119(89)90101-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
A gene (Ecs) encoding a platelet aggregation inhibitor, echistatin (Ecs), has been chemically synthesized. Met at position 28 of the native protein was replaced by Leu in the recombinant Ecs. To express this synthetic gene in Escherichia coli, an expression vector, pJC264, was constructed by inserting portions of the E. coli cheB and cheY gene complex into the plasmid pUC13. High-level expression of the synthetic [Leu-28]Ecs was achieved by its fusion with the E. coli cheY gene in the expression vector. Recombinant [Leu-28]Ecs was liberated from the fusion protein by CNBr cleavage at the Met inserted between the CheY protein and [Leu-28]Ecs. The recombinant [Leu-28]Ecs was purified to homogeneity by reverse-phase high-performance liquid chromatography. The refolded [Leu-28]Ecs was identical to native Ecs in inhibiting platelet aggregation, suggesting that Met at position 28 is not essential for the biological activity of this platelet aggregation inhibitor.
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Affiliation(s)
- Z R Gan
- Department of Biological Chemistry, Merck Sharp & Dohme Research Laboratories, West Point, PA 19486
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22
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Abstract
One hundred and sixty-eight broiler breeder pullets were fed skip-a-day or half the same feed allotment on a daily basis from 5 to 20 wk of age. When weighed on the same day, daily fed birds were significantly larger than skip-a-day-fed birds, but this difference appears to be partly due to feed retained in the digestive tract. Body composition and uniformity were unaffected by feeding regimen.
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Affiliation(s)
- C D Bennett
- Department of Animal and Poultry Science, University of Guelph, Ontario, Canada
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23
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Bennett CD, Leeson S. Water usage of broiler breeders. Poult Sci 1989; 68:617-21. [PMID: 2755889 DOI: 10.3382/ps.0680617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Water usage of daily fed and skip-a-day-fed broiler pullets housed in cages was measured in two trials. Daily fed birds in both trials had free access to water. In Trial 1, skip-a-day-fed birds were restricted to 4 h water every day or only on feed days. In Trial 2, the skip-a-day-fed birds were water restricted 4 h either every day, only on feed days, or had free access to water. Skip-a-day-fed birds tended to drink more water on feed days than on off-feed days but amounts were significantly different only in Trial 2. Water intake of these skip-a-day-fed birds on off-feed days was less than that of comparable birds fed on a daily basis with free access to water. Conversely, skip-a-day-fed birds drank more water on feed days than did daily fed birds (P less than .05) when both groups were given free access to water. Overall mean daily water consumption and spillage were unaffected by feeding or water restriction regimens. The main influence of skip-a-day feeding and water restriction appears to be on the pattern of water consumption and not on overall water usage. Daily feeding increased body weight gain relative to that of birds fed skip-a-day, although water restriction did not influence growth. Metabolizable energy derived from a feed was unaffected by feeding or water restriction regimens.
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Affiliation(s)
- C D Bennett
- Department of Animal and Poultry Science, University of Guelph, Ontario, Canada
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24
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Abstract
This study evaluated the use of hearing aids by patients with hearing threshold levels of 20 dB or less at 500 and 1000 Hz and 35 dB or less at 2000 Hz. Ninety-eight patients completed a 30-day trial with amplification. Six months later, patients were interviewed by telephone and questioned on hearing aid use and perceived unaided and aided difficulty in various listening environments. Results of the study demonstrated that patients with minimal high-frequency hearing loss can benefit from the use of hearing aids. Ninety-two percent of the patients elected to purchase the hearing aids and 85% considered the aids a worthwhile investment after 6 months of use. Patients showed a mean improvement from moderate unaided to slight aided difficulty at work and in general social situations. The only variable that predicted success with hearing aids was degree of unaided difficulty at work. Patients who perceived less unaided difficulty at work were less likely to obtain benefit from the use of the hearing aids.
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Affiliation(s)
- C D Bennett
- Otologic Medical Group, Inc., Los Angeles, California
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25
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Nutt RF, Brady SF, Darke PL, Ciccarone TM, Colton CD, Nutt EM, Rodkey JA, Bennett CD, Waxman LH, Sigal IS. Chemical synthesis and enzymatic activity of a 99-residue peptide with a sequence proposed for the human immunodeficiency virus protease. Proc Natl Acad Sci U S A 1988; 85:7129-33. [PMID: 3050988 PMCID: PMC282137 DOI: 10.1073/pnas.85.19.7129] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Retroviral proteins, including those from the human immunodeficiency virus (HIV), are synthesized as polyprotein precursors that require proteolytic cleavage to yield the mature viral proteins. A 99-residue polypeptide, encoded by the 5' end of the pol gene, has been proposed as the processing protease of HIV. The chemical synthesis of the 99-residue peptide was carried out by the solid-phase method, and the isolated product was found to exhibit specific proteolytic activity upon folding under reducing conditions. Upon size-exclusion chromatography, enzymatic activity was eluted at a point consistent with a dimeric molecular size. Specificity was demonstrated by the cleavage of the natural substrate HIV gag p55 into gag p24 and gag p17, as well as cleavage of small peptide substrates representing processing sites of HIV fusion proteins. The proteolytic action of the synthetic product could be inhibited by pepstatin, an aspartic protease inhibitor.
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Affiliation(s)
- R F Nutt
- Department of Medicinal Chemistry, Merck Sharp & Dohme Research Laboratories, West Point, PA 19486
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26
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Poe M, Bennett CD, Biddison WE, Blake JT, Norton GP, Rodkey JA, Sigal NH, Turner RV, Wu JK, Zweerink HJ. Human cytotoxic lymphocyte tryptase. Its purification from granules and the characterization of inhibitor and substrate specificity. J Biol Chem 1988; 263:13215-22. [PMID: 3047119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
A trypsin-like enzyme (tryptase) has been purified to homogeneity from the granules of a human cytolytic lymphocyte (CTL) line, Q31, by a three-step procedure. By including 0.3% (v/v) Triton X-100 and 1 mg/ml heparin in purification buffers, near total yields of tryptase activity were obtained during the purification. The enzyme, referred to as Q31 tryptase, migrated in polyacrylamide gels with sodium dodecyl sulfate at a position corresponding to 28 kDa with and to 45 kDa without 2-mercaptoethanol. It had an amino-terminal sequence identical to a previously reported human CTL tryptase at 20 of 22 positions identified. It hydrolyzed N alpha-carbobenzyloxy-L-lysyl-thiobenzyl ester (BLT), and this BLT esterase activity was most efficient at slightly alkaline pH and was relatively more active near neutral pH than mouse CTL tryptase. Human alpha 1-protease inhibitor, human antithrombin III, phenylmethanesulfonyl fluoride, and p-aminobenzamidine inhibited the Q31 tryptase. The inhibition by human antithrombin III was rapid enough to be of physiological significance. A survey of oligopeptide p-nitroanilides found that the best substrate for human Q31 tryptase is H-D-(epsilon-carbobenzyloxy)Lys-L-Pro-L-Arg-p-nitroanilide. The Q31 tryptase appears to have broad specificity for amino acid residues at P2 and P3, i.e. at 2 and 3 residues amino-terminal to the scissile bond.
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Affiliation(s)
- M Poe
- Merck, Sharp and Dohme Research Laboratories, Rahway, New Jersey 07065
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27
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Skidgel RA, Bennett CD, Schilling JW, Tan FL, Weerasinghe DK, Erdös EG. Amino acid sequence of the N-terminus and selected tryptic peptides of the active subunit of human plasma carboxypeptidase N: comparison with other carboxypeptidases. Biochem Biophys Res Commun 1988; 154:1323-9. [PMID: 3408501 DOI: 10.1016/0006-291x(88)90284-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Human plasma carboxypeptidase N was purified to homogeneity and its active and inactive subunits were separated. By introducing a novel technique, both forms of the active subunit (Mr = 55,000 and Mr = 48,000) were isolated. N-terminal sequencing of the active subunit of human carboxypeptidase N revealed significant homology with the N-terminal sequence of bovine carboxypeptidase H (43% identity) and to a lesser extent with carboxypeptidase A (29% identity) or carboxypeptidase B (18% identity). The active subunit of carboxypeptidase N was hydrolyzed with trypsin and 4 of the tryptic peptides were isolated by HPLC and sequenced. The sequences of the four peptides were homologous (39-64% identity) with regions of carboxypeptidase H corresponding to the middle (residues 148-175) and C-terminal portion (residues 321-408). These regions had essentially no homology with carboxypeptidase A or B. These data indicate that carboxypeptidase H and the active subunit of carboxypeptidase N may have diverged from a common ancestral gene.
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Affiliation(s)
- R A Skidgel
- Department of Anesthesiology, University of Illinois, Chicago College of Medicine 60612
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28
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Abstract
The enzyme 5-lipoxygenase (5-LO) catalyzes the first two reactions in the pathway leading to the formation of leukotrienes from arachidonic acid. Leukotrienes are potent arachidonic acid metabolites possessing biological activities that suggest a role in the pathophysiology of allergic and inflammatory diseases. To obtain structural information about 5-LO for use in developing anti-inflammatory chemotherapeutic agents, the enzyme was purified from human polymorphonuclear leukocytes and the amino acid sequences were determined for several cyanogen bromide-derived peptides. A cDNA clone encoding a 674-amino acid protein containing all of the derived peptide sequences was isolated from a dimethyl sulfoxide differentiated HL60 cell cDNA library. The mRNA encoding 5-LO was detected only in differentiated HL60 cells and not in the undifferentiated cell line, indicating that the expression of 5-LO in this cell line is transcriptionally regulated. In addition, the human protein displays some amino acid sequence homology with several lipases and significant homology with the partial sequences of soybean and reticulocyte lipoxygenases. Thus, 5-LO appears to be a member of a larger family of related enzymes.
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Affiliation(s)
- R A Dixon
- Department of Virus, Merck Sharp and Dohme Research Laboratories, West Point, PA 19486
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29
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Przysiecki CT, Staggers JE, Ramjit HG, Musson DG, Stern AM, Bennett CD, Friedman PA. Occurrence of beta-hydroxylated asparagine residues in non-vitamin K-dependent proteins containing epidermal growth factor-like domains. Proc Natl Acad Sci U S A 1987; 84:7856-60. [PMID: 2825166 PMCID: PMC299422 DOI: 10.1073/pnas.84.22.7856] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Vitamin K-dependent bovine protein S has been shown to contain a posttranslationally hydroxylated asparagine within a conserved sequence in three of its epidermal growth factor (EGF)-like domains. In a review of amino acid sequences deduced from cDNA data, we have observed that a conserved sequence containing a potential asparagine hydroxylation site exists within EGF-like domains of a variety of functionally diverse proteins. We have studied a number of these and report the presence of erythro-beta-hydroxyasparagine (e-beta Hyn) in three non-vitamin K-dependent proteins: the plasma complement proteins C1r and C1s (where overbar indicates activated form) and the urinary protein uromodulin. For each protein, e-beta Hyn was identified in enzyme digests following the initial observation of erythro-beta-hydroxyaspartic acid (e-beta Hya) in acid hydrolysates of the proteins. e beta Hya and e-beta Hyn residues are detected by a postcolumn derivatization cation-exchange HPLC method herein described. HPLC isolation of the presumptive e-beta Hyn residue from enzyme digests of intact C1r allowed confirmation of its structure by GC/MS. Based upon available cDNA sequence data and observation of e-beta Hya in acid hydrolysates, we suggest other proteins in which e-beta Hyn may occur.
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Affiliation(s)
- C T Przysiecki
- Department of Pharmacology, Merck Sharp & Dohme Research Laboratories, West Point, PA 19486
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30
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Abstract
We have analyzed several lots of epidermal growth factor (EGF) purified from murine submaxillary glands including "receptor grade" EGF from Collaborative Research and EGF from Boehringer Mannheim Biochemicals. New England Nuclear uses "receptor grade" EGF to produce 125I-labeled EGF. Though these reagents are reported to be homogeneous, we found them to be a mixture of six species. A method was developed to separate this mixture into its component parts. The individual components were chemically characterized and tested for biological potency. N-terminal sequence analysis of the unfractionated EGF-mixture reveals three different sequences starting with residues 1, 2, or 3 of the mature peptide. Each component exhibited different degrees of mitogenic and EGF receptor binding activity indicating that the N-terminal region contributes to the biological response. The species representing the complete EGF peptide is the most active species in all biological assays. A rapid method for purification of homogeneous complete EGF from commercial EGF preparations is described.
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Affiliation(s)
- M W Riemen
- Department of Virus and Cell Biology, Merck Sharp and Dohme Research Laboratories, West Point, PA 19486
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31
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Nair BC, Johnson DE, Majeska RJ, Rodkey JA, Bennett CD, Rodan GA. Rat alkaline phosphatase. II. Structural similarities between the osteosarcoma, bone, kidney, and placenta isoenzymes. Arch Biochem Biophys 1987; 254:28-34. [PMID: 3472491 DOI: 10.1016/0003-9861(87)90077-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A mouse monoclonal antibody raised against rat osteosarcoma alkaline phosphatase (AP) was covalently coupled to protein A-Sepharose and used to purify this enzyme from preparations of rat osteosarcoma, calvaria, kidney, and placenta in a single-step procedure. The tissue-specific isoenzymes purified in this manner showed identity in the immunodiffusion reaction with a polyclonal anti-AP antibody, but differed in apparent molecular weight and degree of polydispersity on sodium dodecyl sulfate-polyacrylamide gels. Treatment with N-glycanase abolished these differences, yielding proteins with an apparent molecular weight of 52,000 Da and identical V8 protease digestion patterns. Alkaline phosphatase from these tissues showed no significant difference in amino acid composition and identity in the first 20 N-terminal amino acids. These findings provide structural evidence which supports the hypothesis that the tissue-specific alkaline phosphatase isoenzymes share a common protein sequence subject to different glycosylation pattern.
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32
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Bayney RM, Rodkey JA, Bennett CD, Lu AY, Pickett CB. Rat liver NAD(P)H: quinone reductase nucleotide sequence analysis of a quinone reductase cDNA clone and prediction of the amino acid sequence of the corresponding protein. J Biol Chem 1987; 262:572-5. [PMID: 3100515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
We have determined the nucleotide sequence of a cDNA clone, pDTD55, complementary to rat liver quinone reductase mRNA (Williams, J.B., Lu, A.Y.H., Cameron, R.G., and Pickett, C.B. (1986) J. Biol. Chem. 261, 5524-5528). The cDNA clone contains an open reading frame of 759 nucleotides encoding a polypeptide comprised of 253 amino acids with a Mr = 28,564. To verify the predicted amino acid sequence of quinone reductase, we have been able to align the amino acid sequences of a cyanogen bromide digest of the purified enzyme to the sequence deduced from the cDNA clone. A comparison of the quinone reductase sequence with other known flavoenzymes did not reveal a significant degree of amino acid sequence homology. These data suggest that the quinone reductase gene has evolved independently from genes encoding other flavoenzymes.
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33
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Keller PM, Davison AJ, Lowe RS, Bennett CD, Ellis RW. Identification and structure of the gene encoding gpII, a major glycoprotein of varicella-zoster virus. Virology 1986; 152:181-91. [PMID: 3012867 DOI: 10.1016/0042-6822(86)90383-1] [Citation(s) in RCA: 71] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The genome of varicella-zoster virus (VZV) encodes three major families of glycoproteins (gpI, gpII, and gpIII). mRNA from VZV-infected cells was hybrid selected using a library of VZV recombinant plasmids and translated in vitro; polypeptide products were immunoprecipitated by polyclonal monospecific guinea pig antibodies to gpII. The mRNA encoding a 100-kD polypeptide precipitable by anti-gpII antibodies mapped to the HindIII D fragment near the center of the UL region. DNA sequence analysis of this region of the VZV genome revealed a 2.6-kbp open reading frame (ORF) potentially encoding a 98-kDa polypeptide possessing the characteristics of a glycoprotein. The 100-kDa polypeptide was specified by mRNA isolated by hybrid selection using a plasmid containing part of the 2.6-kbp ORF, and immunoprecipitation of this protein by anti-gpII antibodies and by convalescent zoster serum was blocked specifically by purified gpII. We conclude that the 2.6-kbp ORF encodes gpII. The imputed primary amino acid sequence of gpII shows a high degree of homology to that of herpes simplex virus type 1 (HSV-1) gB, a result consistent with the equivalent map locations of the respective genes in the HSV and VZV genomes and with the recently reported serological cross-reactivity of HSV-1 gB and VZV gpII. Unlike the mature gene products of gB, those of gpII have been described as a pair of glycoproteins with approximate molecular weights of 60 kDa in reducing gels, products of a single glycoprotein species with approximate mol mass of 125-140 kDa in nonreducing gels. Amino-terminal sequences of purified gpII were determined and compared to the imputed amino acid sequence. This comparison implies that the primary translational product is cleaved approximately into halves in vivo and suggests that mature gpII is a disulfide-linked heterodimer.
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Ding GJ, Ding VD, Rodkey JA, Bennett CD, Lu AY, Pickett CB. Rat liver glutathione S-transferases. DNA sequence analysis of a Yb2 cDNA clone and regulation of the Yb1 and Yb2 mRNAs by phenobarbital. J Biol Chem 1986; 261:7952-7. [PMID: 3011803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
We have constructed a cDNA clone, pGTA/C48, which is complementary to the rat liver glutathione S-transferase Yb2 mRNA. Recombinant clone pGTA/C48 contains a cDNA insert of 845 base pairs which overlaps nucleotides 108-952 of the Yb1 cDNA clone, pGTA/C44, described previously by our laboratory (Ding, G. J.-F., Lu, A. Y. H., and Pickett, C. B. (1985) J. Biol. Chem. 260, 13268-13271). Over the protein coding region of the Yb1 and Yb2 cDNA clones there is an 84% nucleotide sequence homology, whereas the 3' untranslated regions are only 32% homologous. The complete amino acid sequence of the Yb2 subunit has been determined from a combination of DNA sequence analysis of pGTA/C48 and conventional protein sequence analysis of the glutathione S-transferase Yb1 Yb2 heterodimer. The Yb2 subunit is comprised of 218 amino acids with a molecular weight of 25,705 and has an amino acid sequence which is 79% homologous to the sequence of the Yb1 subunit. We have utilized the divergent 3' untranslated regions of three rat liver glutathione S-transferase cDNA clones as specific probes to determine the effect of phenobarbital on the level of Yb1, Yb2, and Yc mRNAs. Our results clearly show that the Yb1 and Yb2 mRNAs are elevated approximately 5-6-fold by phenobarbital administration; whereas the Yc mRNA is only modestly elevated by this xenobiotic. Finally, our data suggest that the Yb2 subunit is encoded by a gene(s) which is distinct from the Yb1 gene(s) and provides direct evidence for the existence of multiple glutathione S-transferase Yb genes in the rat.
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Ding GJ, Ding VD, Rodkey JA, Bennett CD, Lu AY, Pickett CB. Rat liver glutathione S-transferases. DNA sequence analysis of a Yb2 cDNA clone and regulation of the Yb1 and Yb2 mRNAs by phenobarbital. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(19)57495-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Dixon RA, Kobilka BK, Strader DJ, Benovic JL, Dohlman HG, Frielle T, Bolanowski MA, Bennett CD, Rands E, Diehl RE, Mumford RA, Slater EE, Sigal IS, Caron MG, Lefkowitz RJ, Strader CD. Cloning of the gene and cDNA for mammalian beta-adrenergic receptor and homology with rhodopsin. Nature 1986; 321:75-9. [PMID: 3010132 DOI: 10.1038/321075a0] [Citation(s) in RCA: 889] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The adenylate cyclase system, which consists of a catalytic moiety and regulatory guanine nucleotide-binding proteins, provides the effector mechanism for the intracellular actions of many hormones and drugs. The tissue specificity of the system is determined by the particular receptors that a cell expresses. Of the many receptors known to modulate adenylate cyclase activity, the best characterized and one of the most pharmacologically important is the beta-adrenergic receptor (beta AR). The pharmacologically distinguishable subtypes of the beta-adrenergic receptor, beta 1 and beta 2 receptors, stimulate adenylate cyclase on binding specific catecholamines. Recently, the avian erythrocyte beta 1, the amphibian erythrocyte beta 2 and the mammalian lung beta 2 receptors have been purified to homogeneity and demonstrated to retain binding activity in detergent-solubilized form. Moreover, the beta-adrenergic receptor has been reconstituted with the other components of the adenylate cyclase system in vitro, thus making this hormone receptor particularly attractive for studies of the mechanism of receptor action. This situation is in contrast to that for the receptors for growth factors and insulin, where the primary biochemical effectors of receptor action are unknown. Here, we report the cloning of the gene and cDNA for the mammalian beta 2AR. Analysis of the amino-acid sequence predicted for the beta AR indicates significant amino-acid homology with bovine rhodopsin and suggests that, like rhodopsin, beta AR possesses multiple membrane-spanning regions.
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Evans BE, Rittle KE, Bock MG, Bennett CD, DiPardo RM, Boger J, Poe M, Ulm EH, LaMont BI, Blaine EH. A uniquely potent renin inhibitor and its unanticipated plasma binding component. J Med Chem 1985; 28:1755-6. [PMID: 3906130 DOI: 10.1021/jm00150a001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Telakowski-Hopkins CA, Rodkey JA, Bennett CD, Lu AY, Pickett CB. Rat liver glutathione S-transferases. Construction of a cDNA clone complementary to a Yc mRNA and prediction of the complete amino acid sequence of a Yc subunit. J Biol Chem 1985; 260:5820-5. [PMID: 2985614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Using polysomal immunoselected rat liver glutathione S-transferase mRNAs, we have constructed cDNA clones using DNA polymerase I, RNase H, and Escherichia coli ligase (NAD+)-mediated second strand cDNA synthesis as described by Gubler and Hoffman (Gubler, U., and Hoffman, B. S. (1983) Gene 25, 263-269). Recombinant clone, pGTB42, contained a cDNA insert of 900 base pairs whose 3' end showed specificity for the Yc mRNA in hybrid-select translation experiments. The nucleotide sequence of pGTB42 has been determined, and the complete amino acid sequence of a Yc subunit has been deduced. The cDNA clone contains an open reading frame of 663 nucleotides encoding a polypeptide comprising 221 amino acids with a molecular weight of 25,322. The NH2-terminal sequence deduced from pGTB42 is in agreement with the first 39 amino acids determined for a Ya-Yc heterodimer by conventional protein-sequencing techniques. A comparison of the nucleotide sequence of pGTB42 with the sequence of a Ya clone, pGTB38, described previously by our laboratory (Pickett, C. B., Telakowski-Hopkins, C. A., Ding, G. J.-F., Argenbright, L., and Lu, A.Y.H. (1984) J. Biol. Chem. 259, 5182-5188) reveals a sequence homology of 66% over the same regions of both clones; however, the 5'- and 3'-untranslated regions of the Ya and Yc mRNAs are totally divergent in their sequences. The overall amino acid sequence homology between the Ya and Yc subunits is 68%, however, the NH2-terminal domain is more highly conserved than the middle or carboxyl-terminal domains. Our data suggest that the Ya and Yc subunits of the rat liver glutathione S-transferases are products of two different mRNAs which are derived from two related yet different genes.
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Boger J, Bennett CD, Payne LS, Ulm EH, Blaine EH, Homnick CF, Schorn TW, Lamont BI, Veber DF. Design of proteolytically-stable, peptidal renin inhibitors and determination of their fate in vivo. Regul Pept Suppl 1985; 4:8-13. [PMID: 3903877 DOI: 10.1016/0167-0115(85)90210-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Leung FC, Taylor JE, Steelman SL, Bennett CD, Rodkey JA, Long RA, Serio R, Weppelman RM, Olson G. Purification and properties of chicken growth hormone and the development of a homologous radioimmunoassay. Gen Comp Endocrinol 1984; 56:389-400. [PMID: 6096203 DOI: 10.1016/0016-6480(84)90081-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Highly purified growth hormone (GH) has been isolated from pituitary glands of chicken (Gallus domesticus), and a specific homologous radioimmunoassay (RIA) has also been developed. The purified chicken GH was active in the rat tibia bioassay and it gave a dose-dependent response which paralleled that of the bovine GH standard. High pressure liquid chromatography revealed that the purified chicken GH was homogenous. Chicken GH had an Rf value of 0.2 in disc electrophoresis, and a MW of 26,000 from sodium dodecyl sulfate-gel electrophoresis. The isoelectric point was estimated to be 7.6 by gel isoelectric focusing. The amino acid composition of chicken GH was found to be similar to that of mammalian GH, and the NH2-terminal amino acid was threonine. Partial sequencing (114 amino acids) of the chicken GH showed 79% homology with bovine GH. An antiserum was developed to the purified chicken GH in a rabbit, and it was used to develop a homologous RIA using 125I-labeled chicken GH as the ligand. The purified chicken GH was iodinated via the lactoperoxidase method to a specific activity of approximately 100 microCi/micrograms. Plasma from chickens, medium from incubation of pituitary glands, and homogenates of pituitary glands gave parallel dilution-response curves with the chicken GH standard. Mammalian GH, prolactin (PRL), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) showed no cross-reaction with the 125I-labeled chicken GH. Purified turkey GH showed parallel dose response with the chicken GH, but purified turkey PRL did not cross-react. Chicken FSH and LH also showed no inhibition of binding. The minimum detectable concentration of the assay was 0.93 ng/tube, and the intraassay and interassay coefficients of variation were 9 and 16%, respectively. The specific binding of 125I-labeled chicken GH to a microsomal fraction isolated from chicken liver was identified, and the specific binding was generally low (1-4%). Turkey PRL, and chicken LH and FSH showed no inhibition of the 125I-labeled chicken GH hepatic binding and the ontogeny of the hepatic GH receptor binding sites in male and female chickens was examined.
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Poe M, Bergstrom AR, Wu JK, Bennett CD, Rodkey JA, Hoogsteen K. Mouse submaxillary gland renin. Purification and properties of minor forms, which include several differently processed forms of the major gene product and a second gene product. J Biol Chem 1984; 259:8358-62. [PMID: 6376503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Three minor forms of renin from the submaxillary glands of male mice called D1, D2, and E have been purified to homogeneity. Their amino acid compositions are identical to the principal form of mouse submaxillary gland renin (renin A), except for 1, 1, and 2 extra arginine residues, respectively. The electrophoretic mobility of renin D2 does not change upon reduction, indicating that its heavy and light chains are linked by more than a disulfide bond. The light chain of renin D1 has an electrophoretic mobility different from the light chain of renin A. Renin D2 is proposed to be renin A with an arginine-arginine dipeptide connecting the carboxyl terminus of the heavy chain to the NH2 terminus of the light chain, with the light chain missing the carboxyl-terminal arginine of renin A. Renin D1 is suggested to be renin D2 with the peptide bond between an arginine and the NH2 terminus of the light chain cleaved. Renin E is proposed to be renin D1 plus the carboxyl-terminal arginine of the light chain. A fourth minor form of male mouse submaxillary renin, called renin B/A, has been purified to homogeneity in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and in isoelectric focusing. Renin B/A seems to be a second renin gene product which is difficult to separate from renin A. Renin B/A has an amino acid composition significantly different from renin A, and all three preparations of B/A had compositions significantly different from one another. For renin B/A, the light chain sequence and the first 53 NH2-terminal residues of its heavy chain sequence were identical to renin A.
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Napier MA, Dewey RS, Albers-Schönberg G, Bennett CD, Rodkey JA, Marsh EA, Whinnery M, Seymour AA, Blaine EH. Isolation and sequence determination of peptide components of atrial natriuretic factor. Biochem Biophys Res Commun 1984; 120:981-8. [PMID: 6539595 DOI: 10.1016/s0006-291x(84)80203-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The independent isolation and sequence determination in our laboratories of three closely related Atrial Natriuretic Factor peptides from rat atria confirm the sequences of ANF peptides reported by Seidah et al and synthesized by Nutt et al [Proc. Natl. Acad. Sci., (1984) in press] and contain the sequences reported by Flynn et al [Biochem. Biophys. Res. Commun. (1983) 117: 859-865] and by Currie et al [Science (1984) 223: 67-69]. In addition, we provide proof for a C-terminal tyrosine rather than tyrosine amide in our isolated peptides.
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Brady SF, Cochran DW, Nutt RF, Holly FW, Bennett CD, Paleveda WJ, Curley PE, Arison BH, Saperstein R, Veber DF. Synthesis and conformational study of a cyclic hexapeptide analog of somatostatin containing dehydrophenylalanine. Int J Pept Protein Res 1984; 23:212-22. [PMID: 6142022 DOI: 10.1111/j.1399-3011.1984.tb02712.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A cyclic hexapeptide analog of somatostatin, cyclo-(Pro-delta z-Phe-D-Trp-Lys-Thr-Phe) (II) has been synthesized by a combination of solid phase and solution methodology. It shows a potency for inhibition of growth hormone release in vitro about one-tenth that of the corresponding saturated analog, cyclo-(Pro-Phe-D-Trp-Lys-Thr-Phe) (I). N.m.r. studies indicate comparable backbone conformations for analogs I and II. However, the sum of our findings from biological evaluation and solution physical data suggest that on the receptor the position-7 phenyl ring of I is adopting a conformation which differs from that of one of the major solution conformers defined previously by n.m.r. studies.
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Guidotti A, Forchetti CM, Corda MG, Konkel D, Bennett CD, Costa E. Isolation, characterization, and purification to homogeneity of an endogenous polypeptide with agonistic action on benzodiazepine receptors. Proc Natl Acad Sci U S A 1983; 80:3531-5. [PMID: 6304714 PMCID: PMC394079 DOI: 10.1073/pnas.80.11.3531] [Citation(s) in RCA: 402] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
A brain polypeptide termed diazepam-binding inhibitor (DBI) and thought to be chemically and functionally related to the endogenous effector of the benzodiazepine recognition site was purified to homogeneity. This peptide gives a single band of protein on NaDodSO4 and acidic urea gel electrophoresis. A single UV-absorbing peak was obtained by HPLC using three different columns and solvent systems. DBI has a molecular mass of approximately equal to 11,000 daltons. Carboxyl-terminus analysis shows that tyrosine is the only residue while the amino-terminus was blocked. Cyanogen bromide treatment of DBI yields three polypeptide fragments, and the sequences of two of them have been determined for a total of 45 amino acids. DBI is a competitive inhibitor for the binding of [3H]diazepam, [3H]flunitrazepam, beta-[3H]carboline propyl esters, and 3H-labeled Ro 15-1788. The Ki for [3H]-diazepam and beta-[3H]carboline binding were 4 and 1 microM, respectively. Doses of DBI that inhibited [3H]diazepam binding by greater than 50% fail to change [3H]etorphine, gamma-amino[3H]butyric acid, [3H]-quinuclidinyl benzilate, [3H]dihydroalprenolol, [3H]adenosine, and [3H]imipramine binding tested at their respective Kd values. DBI injected intraventricularly at doses of 5-10 nmol completely reversed the anticonflict action of diazepam on unpunished drinking and, similar to the anxiety-inducing beta-carboline derivative FG 7142 (beta-carboline-3-carboxylic acid methyl ester), facilitated the shock-induced suppression of drinking by lowering the threshold for this response.
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Poe M, Wu JK, Florance JR, Rodkey JA, Bennett CD, Hoogsteen K. Purification and properties of renin and gamma-renin from the mouse submaxillary gland. J Biol Chem 1983; 258:2209-16. [PMID: 6337154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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Poe M, Wu JK, Florance JR, Rodkey JA, Bennett CD, Hoogsteen K. Purification and properties of renin and gamma-renin from the mouse submaxillary gland. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(18)32909-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Abstract
The positive inotropic effect of anthopleurin-A (AP-A) was studied in vitro on isolated cat heart papillary muscles and in vivo in anesthetized and conscious dogs. In vitro, in low Ca2+ solution (1.27 mM), AP-A increased the force of contractions of isolated cat heart papillary muscles at concentrations from 0.2 x 10(-8) M and higher; on a molar basis, AP-A was more than 200 times as potent as digoxin and on a weight basis, 33 times as potent. In vivo in anesthetized dogs, AP-A at 0.2 microgram/kg/min i.v. increased myocardial contractile force; the geometric mean dose of AP-A required to increase the contractile force by 25% was 2.6 micrograms/kg; the corresponding dose of digoxin (infused at 2.8 micrograms/kg/min) was 107.4 micrograms/kg. The geometric mean lethal dose of AP-A for 8 dogs was 19.3 and that of digoxin 263.2 micrograms/kg i.v. The therapeutic index of AP-A was significantly higher than that of digoxin. All animals that received either AP-A or digoxin died in ventricular fibrillation. The reversal of t-wave was typical for AP-A. As measured by left ventricular pressure telemetry, AP-A, 2 micrograms/kg i.v. single dose, increased LV dp/dt max in conscious dogs for longer than 2 hr.
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Spiess J, Rivier JE, Rodkey JA, Bennett CD, Vale W. Isolation and characterization of somatostatin from pigeon pancreas. Proc Natl Acad Sci U S A 1979; 76:2974-8. [PMID: 288081 PMCID: PMC383733 DOI: 10.1073/pnas.76.6.2974] [Citation(s) in RCA: 81] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Most of the somatostatin-like activity from pigeon pancreas was found to correspond to small species with an apparent molecular weight of 1500--2500. This species was isolated under conditions minimizing intermolecular interactions and protease activities. The isolated product was characterized by two somatostatin radioimmunoassays, a bioassay, endgroup determination, and amino acid analysis. The structure of the isolated compound was determined to be H-Ala-Gly-cyclo-(Cys-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Cys)-OH. Additionally, small amounts of des-Ala1-somatostatin, a possible degradation product of pancreatic somatostatin, and a large somatostatin-like species with an apparent molecular weight of 11,000--12,500 were detected. It is concluded that the main somatostatin-like polypeptide isolated from pigeon pancreas is identical to the mammalian hypothalamic tetradecapeptide somatostatin.
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Bennett CD, Rodkey JA, Sondey JM, Hirschmann R. Dihydrofolate reductase: the amino acid sequence of the enzyme from a methotrexate-resistant mutant of Escherichia coli. Biochemistry 1978; 17:1328-37. [PMID: 350268 DOI: 10.1021/bi00600a030] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The determination of the amino acid sequence of the enzyme dihydrofolate reductase (5,6,7,8-tetrahydrofolate:NADP+ oxidoreductase, EC 1.5.1.3) from a mutant of Escherichia coli B is described. The 159 residues were positioned by automatic Edman degradation of the whole protein, of the reduced and alkylated cyanogen bromide fragments, and of selected tryptic, chymotryptic, and thermolytic digestion products. An N-bromosuccinimide produced fragment of the largest cyanogen bromide peptide was also used in the sequence determination.
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Williams MN, Bennett CD. Effect of cysteine modification on dihydrofolate reductase from a methotrexate-resistant strain of Escherichia coli B. Identification of modified residues. J Biol Chem 1977; 252:6871-7. [PMID: 330537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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